 1974 1.8L engine fast idle then stalls, Fuel injection issues |
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| tshih914 |
 Feb 19 2023, 11:45 PM
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Member  Group: Members Posts: 79 Joined: 17-July 05 From: central NJ Member No.: 4,426  |
My 1.8L 914-4 with stock Bosch L?-Jetronic FI after being stored several years started to develop a hard to start problem. When finally started would stall when I give the gas pedal any input to raise the revs. I suspect there was some kind of intake air leak and while fiddling around had a backfire which blew the AF meter which I had Pelicanparts repaired. After replacing the fuel lines with the stainless ones from Tangerine Racing and flushing out the fuel system with Techron the engine started to run normally for a short time. Now the engine can be started and fast idles at 3000 rpm but again any input to rev up the engine results in stalling. The idle adjustment screw at the base of the throttle housing is fully closed. Any suggestions on how to fix?
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Replies
| Van B |
Feb 20 2023, 06:45 PM
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#2
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Senior Member Group: Members Posts: 1,618 Joined: 20-October 21 From: WR, GA Member No.: 26,011 Region Association: None 
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@wonkipop . What he described is exactly what happened when I started the car and forgot to plug in the AFM. Steve tried it and the same thing happened for him. You tried it and it didn’t work. That’s when I realized my fuel pump wiring was wrong as yours was OE and Steve and I had a different setup from the relocation to the front.
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| wonkipop |
Feb 20 2023, 06:52 PM
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#3
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Advanced Member Group: Members Posts: 4,667 Joined: 6-May 20 From: north antarctica Member No.: 24,231 Region Association: NineFourteenerVille
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QUOTE(Van B @ Feb 20 2023, 06:45 PM)  @wonkipop . What he described is exactly what happened when I started the car and forgot to plug in the AFM. Steve tried it and the same thing happened for him. You tried it and it didn’t work. That’s when I realized my fuel pump wiring was wrong as yours was OE and Steve and I had a different setup from the relocation to the front. yeah - see my post above where i edited it. memory recall was coming back. i'm getting old and my ECU is a bit hard to fire up. but i was remembering you did something exactly like this. i'm thinking his pump wiring is letting the engine run because it does not need the AFM contacts operating at idle to do it. and i'm thinking that maybe his EFI plug and harness from AFM to ECU is possibly kaput. like despite being plugged in its not actually connecting. so as you gas it its all over. all air and suddenly no fuel. the ECU is not opening the injectors. no signal? would pull those plugs out at both ECU and AFM and given them a good clean first of all. checking for corrosion. then i guess test it all as per factory manual. |
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Posts in this topic
tshih914 1974 1.8L engine fast idle then stalls Feb 19 2023, 11:45 PM
Van B Check to make sure your AFM is plugged in first. Feb 20 2023, 01:28 AM
wonkipop
Check to make sure your AFM is plugged in first.
... Feb 20 2023, 01:38 AM Geezer914 1+ on the AFM not being connected. Check for vacu... Feb 20 2023, 06:48 AM tshih914
1+ on the AFM not being connected. Check for vac... Feb 20 2023, 11:02 AM wonkipop
1+ on the AFM not being connected. Check for va... Feb 20 2023, 02:33 PM Van B
[quote name='Geezer914' post='3059382' date='Feb ... Feb 20 2023, 02:51 PM wonkipop
1+ on the AFM not being connected. Check for va... Feb 20 2023, 05:11 PM dr914@autoatlanta.com for the hell of it check the throttle body boot fo... Feb 20 2023, 11:17 AM r_towle
for the hell of it check the throttle body boot f... Feb 28 2023, 08:57 PM tshih914
for the hell of it check the throttle body boot ... Feb 28 2023, 09:13 PM rhodyguy Would a vacuum leak down stream of AFM result in a... Feb 20 2023, 01:22 PM wonkipop
Would a vacuum leak down stream of AFM result in ... Feb 20 2023, 02:17 PM Van B @wonkipop What alerts me is the no change in idle... Feb 20 2023, 02:57 PM wonkipop
[b]@[url=http://www.914world.com/bbs2/index.php?s... Feb 20 2023, 03:20 PM Van B Yeah, I know, but I don’t care about California ... Feb 20 2023, 03:33 PM wonkipop
Yeah, I know, but I don’t care about California... Feb 20 2023, 03:49 PM jim_hoyland All the above; L-Jet requires that there are no va... Feb 20 2023, 03:52 PM wonkipop @Van B
thinking about his problem there are two ... Feb 20 2023, 04:13 PM tshih914
@[url=http://www.914world.com/bbs2/index.php?show... Feb 22 2023, 07:36 PM Van B Boy does that all sound familiar.
I’d still lik... Feb 20 2023, 04:24 PM wonkipop
Boy does that all sound familiar.
I’d still li... Feb 20 2023, 04:39 PM porschetub
Boy does that all sound familiar.
I’d still l... Feb 20 2023, 08:34 PM wonkipop
[quote name='Van B' post='3059531' date='Feb 20 ... Feb 21 2023, 02:57 AM wonkipop @Van B
which is to say as i suspected that high ... Feb 20 2023, 06:56 PM Geezer914 Go to Jeff Bowlsby's web site
and get the Ljet... Feb 20 2023, 07:13 PM JeffBowlsby You might also check the quality of the contacts i... Feb 20 2023, 11:58 PM wonkipop
You might also check the quality of the contacts ... Feb 21 2023, 03:05 AM Van B Whatever you have back there by the batter near wh... Feb 22 2023, 08:19 PM tshih914
Whatever you have back there by the batter near w... Feb 23 2023, 04:46 AM Van B Ok. Glad that thing wasn't some decel valve ri... Feb 23 2023, 05:54 AM Geezer914 Got rid of all that shit, the decel valve and the ... Feb 23 2023, 08:45 AM rjames
Got rid of all that shit, the decel valve and the... Feb 23 2023, 11:50 AM wonkipop
Got rid of all that shit, the decel valve and th... Feb 23 2023, 11:54 AM rhodyguy Curious. What kind of condition are the oil fill t... Feb 23 2023, 11:58 AM wonkipop ok @tshih914
[b]@[url=http://www.914world.com/... Feb 23 2023, 12:00 PM tshih914
ok [b]@[url=http://www.914world.com/bbs2/index.p... Feb 23 2023, 07:58 PM tshih914
ok [b]@[url=http://www.914world.com/bbs2/index.... Feb 23 2023, 08:16 PM Van B @wonkipop if the decel valve is full flow, it cou... Feb 23 2023, 02:50 PM wonkipop
[b]@[url=http://www.914world.com/bbs2/index.php?s... Feb 23 2023, 03:58 PM wonkipop ok
@Van B and [b]@[url=http://www.914world.com/... Feb 23 2023, 06:50 PM wonkipop wow @tshih914
that was a quick test and reply.
... Feb 23 2023, 09:01 PM Van B Definitely sounds like the AFM is doing stuff… b... Feb 23 2023, 09:41 PM tshih914
Definitely sounds like the AFM is doing stuff… ... Feb 25 2023, 04:35 PM tshih914
Definitely sounds like the AFM is doing stuff…... Feb 25 2023, 04:36 PM wonkipop @tshih914
we are getting somewhere.
this time it... Feb 25 2023, 05:56 PM Van B @tshih914
The decel valve is on the other side. ... Feb 25 2023, 06:45 PM Van B Yeah this is all wrong. You’ve got the wrong par... Feb 25 2023, 06:49 PM wonkipop @Van B .
i think he has got it right.
he seems to... Feb 25 2023, 07:22 PM wonkipop i think he has pulled this hose out and capped the... Feb 25 2023, 07:26 PM wonkipop where i am going with my thinking @Van B is
1. ... Feb 25 2023, 07:44 PM Van B Looks to me then like the decel valve is connected... Feb 25 2023, 07:54 PM wonkipop @Van B .
yes i noticed that kink in the small vac... Feb 25 2023, 08:29 PM wonkipop i just watched your video @Van B .
your decel is ... Feb 25 2023, 08:56 PM tshih914 I have every vacuum hose hooked up the same as the... Feb 26 2023, 07:57 AM wonkipop
I have every vacuum hose hooked up the same as th... Feb 26 2023, 12:53 PM Van B
I have every vacuum hose hooked up the same as th... Feb 26 2023, 12:58 PM wonkipop
I have every vacuum hose hooked up the same as t... Feb 26 2023, 01:03 PM r_towle When I am hunting for a failure in the vacuum syst... Feb 25 2023, 09:03 PM Van B 74 L-Jetronic needs the distributor vacuum for any... Feb 25 2023, 09:19 PM wonkipop
74 L-Jetronic needs the distributor vacuum for an... Feb 26 2023, 12:37 AM nihil44 I've come in late here and haven't read al... Feb 26 2023, 01:43 AM wonkipop
I've come in late here and haven't read a... Feb 26 2023, 01:54 AM Geezer914 Last resort is to do a smoke test. Search on you ... Feb 26 2023, 06:12 AM Geezer914 I had a hell of a time finding a vacuum leak. It ... Feb 26 2023, 09:39 AM Van B Ok so, I checked my AFM to see what I settled on f... Feb 26 2023, 12:50 PM wonkipop ps
in addition to blocking off snorkel the only ot... Feb 26 2023, 12:58 PM Van B
ps
in addition to blocking off snorkel the only o... Feb 26 2023, 01:00 PM wonkipop two suggestions by other members re injector seals... Feb 26 2023, 01:58 PM tshih914
two suggestions by other members re injector seal... Feb 26 2023, 03:23 PM wonkipop
two suggestions by other members re injector sea... Feb 26 2023, 03:50 PM wonkipop direct link to AA vac hose kit.
http://www.autoat... Feb 26 2023, 03:58 PM tshih914
direct link to AA vac hose kit.
http://www.autoa... Feb 26 2023, 05:18 PM wonkipop
[quote name='wonkipop' post='3061145' date='Feb 2... Feb 26 2023, 06:36 PM nihil44 Here is the gasket on the AFM connector which wasn... Feb 26 2023, 05:47 PM nihil44 I have been pursuing running issues and vac leaks ... Feb 26 2023, 06:28 PM wonkipop love your work @nihil44 Feb 26 2023, 06:39 PM tshih914
love your work @[url=http://www.914world.com/bbs... Feb 27 2023, 09:45 PM wonkipop
love your work [b]@[url=http://www.914world.com... Feb 28 2023, 02:26 AM Van B See the little hole near the front right off the A... Feb 28 2023, 06:51 AM tshih914
See the little hole near the front right off the ... Feb 28 2023, 07:44 PM wonkipop
See the little hole near the front right off the... Feb 28 2023, 07:51 PM tshih914
[quote name='tshih914' post='3061665' date='Feb 2... Feb 28 2023, 08:47 PM tshih914
[quote name='tshih914' post='3061665' date='Feb ... Feb 28 2023, 09:10 PM wonkipop
[quote name='tshih914' post='3061665' date='Feb ... Feb 28 2023, 10:40 PM Van B Have you adjusted the decel valve or tested it to ... Feb 28 2023, 08:07 PM Van B @wonkipop quit being so scared to that mean AFM. ... Feb 28 2023, 08:09 PM wonkipop
[b]@[url=http://www.914world.com/bbs2/index.php?s... Feb 28 2023, 10:23 PM Van B Thats too low IMO. I posted the link to my thread ... Feb 28 2023, 08:53 PM Van B Diaphragm is rubber. It gets hard and less flexibl... Feb 28 2023, 09:58 PM wonkipop @tshih914
i knew i had this filed away but could... Mar 2 2023, 09:55 PM wonkipop here is the rest of it.
its an idiots guide.
which... Mar 2 2023, 10:15 PM tshih914
here is the rest of it.
its an idiots guide.
whic... Mar 3 2023, 10:11 PM tshih914
[quote name='wonkipop' post='3062180' date='Mar 2... Mar 3 2023, 10:12 PM tshih914
[quote name='wonkipop' post='3062180' date='Mar ... Mar 3 2023, 10:13 PM tshih914
[quote name='tshih914' post='3062427' date='Mar 3... Mar 3 2023, 10:18 PM Van B When you pinch the AAV hose, and the rpm drops to ... Mar 3 2023, 10:42 PM Van B One other thing, I’m not understanding how you j... Mar 3 2023, 10:43 PM |
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